Physical Chemistry Essay Example

Physical Chemistry

The law of multiple proportions that posits that when 2 chemical elements combine to produce more than one likely compound then the proportion of the second element’s mass that joined with a specific mass of the first element will be represented as proportions of whole numbers (Niaz, 2001). The results of this laid the foundation for Dalton’s Atomic Laws. These are made up of five theorems. The first theorem posits that an element, in its unmixed state, is made up of particles referred to as atoms. The second posits that all the atoms in a particular element are similar. The third posits that distinguishing atoms belonging to different elements can be done by using their different atomic weights. Fourth, that compounds are made when atoms are combined. And lastly, it is not possible to either create or destroy atoms in a chemical reaction, the only thing that changes is the grouping. Previous chemists were not able to make the breakthroughs that Dalton made because in the times before him the laboratory instruments that existed were very crude and could not make small, precise measurements.Dalton’s development on the atomic model made it possible for more researchers and scholars to study the atom in greater detail. In 1897, J. Thomson discovered the electron, and his discovery opened people’s eyes to the fact that atoms were in fact made up of tinier particles. By this time however, discovery of the atomic nucleus was still years away, and therefore the plum pudding model was proposed in 1904. The model states that the atom is composed of electrons which drift freely in a soup made of positive charges. The model did not explain how the electrons were organized inside the atom (Hon & Goldstein, 2013). In 1911 Ernest Rutherford established the planetary model of the atom that stated that the protons were found in the nucleus of the atom and then put the electrons in orbiting paths round the nucleus (Nagendrappa, 2011). Niels Bohr further developed Rutherford’s model by putting forward then idea that the orbiting electrons could only move around the nucleus in definite orbits at distinct energy levels around the atom’s nucleus (Prasad, 2013).John Dalton played a crucial role in setting the ball in motion regarding studies about the nature of the atom, and how the atoms in an element came together in various proportions to form compounds. He pioneered the way for the likes of J. Thomson, Ernest Rutherford and Niels Bohr to carry

Niaz, M., 2001. How Important are the Laws of Definite and Multiple Proportions in Chemistry and Teaching Chemistry? – A History and Philosophy of Science Perspective. Science & Education, 10(3), pp. 243-266.